This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A153883 #11 May 05 2023 18:12:13 %S A153883 0,1,3,4,6,7,12,13,15,16,18,19,24,25,27,28,30,31,36,37,39,40,42,43,60, %T A153883 61,63,64,66,67,72,73,75,76,78,79,84,85,87,88,90,91,96,97,99,100,102, %U A153883 103,120,121,123,124,126,127,132,133,135,136,138,139,144,145,147,148 %N A153883 a(n) = A153880(n)/2. %o A153883 (Scheme) %o A153883 ; MIT Scheme %o A153883 (define (A153883 n) (let loop ((n n) (z 0) (i 2) (f 1)) (cond ((zero? n) z) (else (loop (floor->exact (/ n i)) (+ (* f (modulo n i)) z) (1+ i) (* f (+ i 1))))))) %Y A153883 Cf. A153880. %K A153883 base,nonn %O A153883 0,3 %A A153883 _Antti Karttunen_, Jan 03 2009